Nintendo DS Wi-Fi Help?

I have no clue how to get this "easy to use" wi-fi to work! I have tried and tried for endless hours and still cannot get it to activate. When I got my router connected, but there was a red padlock. I tried to configure the settings, but it still doesn't work. I get error codes 52000 and 52100. Please give me a step by step tutorial, their website is no help at all! Thanks so much!